BANGKOK — The embattled government of Prime Minister Yingluck Shinawatra declared the imposition of emergency rule in Bangkok and surrounding areas on Tuesday, suggesting a more aggressive posture toward protesters who have occupied parts of the city during the past two months and are seeking to overthrow the government.

But officials said they had no plans to crack down on protesters, who have escalated their campaign over the past week by blocking government offices, taking over major intersections and staging daily marches across Bangkok. The emergency decree enacted Tuesday gives the government the power to invoke curfews, censor the news media, disperse gatherings and use military force to “secure order.”

Surapong Tovichakchaikul, Thailand’s foreign minister, said the move was necessary because protesters had broken the law by blocking government offices and banks in recent days and threatening and harassing government officials. The decree will “allow the democratic process and Thailand to move forward,” he said.

Protesters have been attacked by unknown assailants in recent days. Three grenade attacks left one person dead and dozens injured. The government and the protesters have blamed each other for those attacks.

The emergency decree, which is valid for 60 days, was passed under the same law that a different government used in 2010 to start a military crackdown that left dozens of people dead. Underlining the seesaw power struggle that has gripped Thailand for the better part of the past eight years, the man responsible for the crackdown four years ago, Suthep Thaugsuban, a former deputy prime minister, is now leading the antigovernment protests.

“I know about this well,” Mr. Suthep said to his supporters, discussing the decree. He stepped down from power after his party lost a general election in 2011.

“We will keep fighting until we win,” Mr. Suthep said, describing his protest movement as nonviolent and distinct from the “terrorists” who protested against him in 2010.

Mr. Suthep, who faces murder charges related to the 2010 crackdown, renewed a threat late on Tuesday to shut down Thailand’s air traffic control office, but he also said he would rest on Wednesday for medical reasons.

In recent weeks the government has been lauded by foreign governments, including the United States and European countries, for its restraint in handling the protests. The police have not tried to arrest Mr. Suthep despite a court-issued warrant for rebellion against the state.

In addition to the emergency decree, the government on Tuesday put a combative government minister and former police officer, Chalerm Yubamrung, in charge of security.

Mr. Suthep is trying to disrupt elections scheduled for Feb. 2 that Ms. Yingluck and her allies are considered almost certain to win. The opposition Democrat Party, which is allied with Mr. Suthep, is boycotting the election.

In a country long plagued by corruption, protest leaders say Ms. Yingluck’s party has taken graft to a new level and is subverting democracy. Protesters are calling for an unelected “people’s council” to run the country and carry out political overhauls. The government says protesters are in the streets because they cannot win at the ballot box.

The debilitating and complex power struggle in Thailand has put into question the future of Thai democracy. Ms. Yingluck and her brother, Thaksin Shinawatra, the founder of the most successful political movement in modern Thai history, have broad support in the north of the country. The protesters draw their support from Bangkok and the south. The powerful Thai military, which has staged a dozen coups in modern Thai history, is being courted by both sides.

A version of this article appears in print on , Section A, Page 4 of the New York edition with the headline: Thai Leaders Declare State of Emergency in Bangkok. Order Reprints | Today’s Paper | Subscribe